Mythical Viking 'Sunstone' could have really worked: study

Bringing the realm of ancient myth into reality, scientists say they have found evidence that the Vikings could have used a 'sunstone' crystal to navigate from northern Europe to North America.

Researchers from the University of Rennes in France say a calcite crystal that was discovered in the wreckage of a 421-year-old ship could be the substance once thought to be no more than an ancient Viking myth.

The crystal – called an Iceland spar-- was found 30 years ago amid the wreckage of a ship that sunk off the coast of Alderney in the Channel Islands in 1592.

In a report published in The Proceedings of The Royal Society on Wednesday, the study’s authors say the crystal could be used to determine the sun's location with an accuracy of one degree, even when it was invisible to the naked eye.

"We demonstrate that Alderney-like crystals could really have been used as an accurate optical sun compass as an aid to ancient navigation, when the Sun was hidden by clouds or below the horizon," the study said.

The study's authors said their findings may help identify other crystals used by the Vikings.

"The evolution of the Alderney crystal lends hope for identifying other calcite crystals in Viking shipwrecks, burials or settlements."